Generally, the color shift in a liquid crystal display can be solved by the charge sharing performed among a plurality of capacitors in a pixel. Please refer to FIG. 1, which is a schematic circuit view of a conventional liquid crystal pixel circuit for solving the color shift problem. As shown, in the conventional liquid crystal pixel circuit, the main pixel is controlled by the gate line Gate1 and is configured to, through the transistor T1, receive data from the data line Data and then store the received data in the storage capacitor Cst1; and the sub pixel is controlled by the gate line Gate1 and is configured to, through the transistor T2, receive data from the data line Data and then store the received data in the storage capacitor Cst2. In addition, the sub pixel is also controlled by the gate line Gate2 and is configured to, through the transistor T3, make the storage capacitor Cst2 and the storage capacitor Ccsb have the charge sharing. Through the aforementioned circuit structure, the liquid crystal pixel circuit of FIG. 1 can appropriately control the ratio of the voltage stored in the storage capacitor Cst1 to the voltage stored in the storage capacitor Cst2; thus, the liquid crystal capacitors Clc1 and Clc2 can be driven by predetermined voltages thereby eliminating the color shift when image is being displayed.
However, with the technology development, the current liquid crystal display has rapidly-increasing resolution and image update frequency. Accordingly, more data stored in the pixel circuits is needed to be updated in the same time period in response to the increasing resolution; a shorter time is needed for updating the data stored in the pixel circuits in response to the increasing image update frequency; or a shorter time is needed for updating the data stored in the pixel circuits in response to both of the increasing resolution and the increasing image update frequency. Thus, for each one of the pixel circuits, the charging time for storing the data transmitted on the data line Data to the storage capacitors Cst21 and Cst2 is getting shorter.
Because the charging time can be used by the pixel circuit is reduced, the storage capacitors Cst21 and Cst2 may not be fully charged and which may consequently lead to that the voltages stored in the storage capacitors Cst21 and Cst2 may not have the same voltage level. Once the storage capacitors Cst21 and Cst2 have different stored voltages, the ratio of the voltage stored in the storage capacitor Cst2 to the voltage stored in the storage capacitor Cst1 may not reach to the expected value after the charge sharing; and consequentially, the color shift may occur again during the image displaying process.